Pneumatic dispatch system



June 16, 1931. EMERSON 1,810,269

PNEUMATIC DISPATCH SYSTEM Filed Aug. 2. 1929 4 Sheets-Sheet l L F A June16, 1931. M. EMERSON PNEUMATIC DISPATCH SYS'I'BI Filed Aug. 2. 1929 4Shoots-Sheet 2 lll .vitlx llllls It ESE June 16, 1931. M. L. EMERSON1,810,269

PNEUMATIC DISPATCH SYSTEM Filed Aug; 2. 1929 4 Sheets-Sheet 5 j7zdeziar' fie; for L la? wra 1/ June 16, 1931. EMERSON 7 1,810,269

PNEUMATIC DISPATCH SYSTEM,

Filed Aug. 2. 1929 4 Sheets-Sheet .4

9| I o 170 96 t Y 8 J14 (a 101 112* 06 7 1!? l 1 Z100 z b zr/ .01

Patented June 216, 193i untrue srarus PATENT orifice; j

neuron L. ire-neon. or ,sYnAcusn; new YORK, Assisnoero rnnrnusouconrenv;

or srnecusn, new YORK, a conroenrion or raessecnusn'rrs j PNEUMATIC.nIsrArcH sYsrnM' Application filed August 2,1929. Serial No. 382,876.

This invention relates to an iinprovement apneumatic dispatch system,and more 'particularlygin a system, offthe single transmission tuhetyp'e wherein the carrier may '5 be sent in one direction throughthetube by positive pressure andin the opposite direction throughthe'tube by negative pressure or vacuum. 2

. The primary object of this invention is to 19 provide a system of thesingle transmission tube type shown in the patent to Fordyce No.873,531,! dated December 10,1907, and the patent to Maclaren No.1,396,449,, dated November 8., 1921, but diilering therefrom in 35certain features and details of [structure whereby the operation of thesystem is made more. accurate and practically automatic.

' A further object of the invention is to provide in thersystein meansnormally main taining a minimum-"flow of air through thetransmissionftubeand responsive to areductlion in suchfiow, resultingfrom the insertion of a carrier in the tube, for initiating a car'-rier' impelling flow through the tube and means for initiating a;carrier impelling flow through the tube in the. opposite direction.

A other object of theinvenrtion is toproride in the system a valve whichnormally permits the nraintenanceuof the minimum 56 liowbut which cutsoil" such flow upon the initiation of the carrier: impelling flowin thedirection opposite to that of the mini mu m'flow. r

Other objects of the invention wi l be apparen-tto'on-e skilled in theart from anes aln-ination v of thefollowing specification wherein one;embodiment thereof is described aud oi the drawings which form a 2 partthereof, and in which Y Fig. 1 is a view more or less diagrammatic,illustrating one embodiment of my invention in a pneumatic dispatchsystem; 7 Figs. 2 and 3 are sectionalviews, on an enlarged scale, of thevalve construction, Fig.

2 illustrating the valve in its normal position as when 'aminimum flowis being maintained when a earrierimpell-ing flow by nege ative' orsuction-pressure is being created;

and Figr 3 illustratingthea alve in the position; it occupies when acarrier inipelling flow by positive pressure is being created;

Fig. 4 is a sectional viewtaken along the line 4'4e ofFig. 2; p

Fig. 5 is a sectional view illustrating afportion of thenegativepressure tube and the power controlthere-for; e y

Fig; 6 is a side elevation illustrating a por-, tion ofthe positivepressure tube. and the power control therefor;

Fig. 7 is asectional View similar to Fig. 5 of the pressure powercontrol;

Fig. 8 is a plan view taken along the line 8.8 of Fig.7; Fig. 9 is aside elevation of thepressure power control unit; I Fig. 10 is anenlarged sectional View of the manually operated actuator for thepressure power control and by whicha carrier impelling flow in the tubeby positive pressure is initiated; i

Fig. 11 is an enlarged sectional view taken" alon'gthe line 1111 of Fig10f the central station door and latch;

Fig. 12 is an elevation of 'the'la-tch shown in Fig. 11 taken in thedirection of the arrow 12. 1

The system illustrated Fig.1 comprises briefly a central station IA, asubstation B, a pressure blower C, and a vacuum blower D. Connecting thestations A and B is a transmi'ssion tube terminating at the substat'ionxB in an open carrier discharging out- I let 21 and an open carrierreceiving inlet 22.- Located below the outlet 21 is a carrier basket23,' shown as supported upon a platform 24. Leading to the centralstation A issan air conduit 25 connected by air tubes 26, 27' to. drums28 and 29 respectively; Positive pressureis maintained in the drum 28 bythepressure blower C and negative pressure is maintained in the drum 29by the vacuum blower D..= "The air tube .27 is providedwith a vacuumtime-0E power control 30 and the tube 26-is provided with a pressuretime-oil "power control 31.

i The tubes 26 and 27 are joined to conduit 25' jby'a coupling-which,-inthe illustrative embodiment, comprises a. T=shaped casing 82: made up oftwo sectionsBB, 34; having ob.

liquely faced abutting surfaces. Mounted within the casing 32 is a valvemechanism 35 which is shown in detail in Figs. 2 and 3. The sections 33and 34, which receive the tubes 26 and 27, are provided with inclinedseats 36 and 37, respectively, with which engage a flapper valve 38mounted upon a shaft '39 supported in a recess 40 formed in the section34 of the casing. A spring 41 on the shaft 39 normally holds the valve38 in contact with the seat 36, as shown in Fig. 2. Mounted upon theshaft 39 is an arm 42 carrying at its outer end a plate valve 43 whichnormally closes an orifice 44 formed in the section 34 When however thevalve 38 leaves the seat 36, the arm 42 and valve 43 open the orifice 44thus providing a free escape to the atmosphere of the air in the tube27.

The vacuum time-off power control 30 may be of any desired type, and Ihave elected to show herethe type set forth in the copending applicationof James T. Cowley, Serial No. 317,857, filed November 7, 1928 nowPatent No.1,740,500. This control (see Fig. 5) comprises a casinginserted between and providing a passage in alignment with two sectionsof the tube 27. Supported in the easing is a shaft 51 extendingtransversely of the passage upon which is carried a valve 52 preferablyof the butteryfly type by which the passage in the casing is controlled.At one side of the casing 50 is provided a l1ousing 53 consisting ofsections 54, 55 between the edges of which a diaphragm 56 is clamped.The diaphragm divides the space within the housing into chambers 57 and58, the latter being open to the atmosphere through a port 59. Thechamber 57 normally communicates with the passage through the casing 50by a port 60 and communicates with theatmosphere through a bleed passageI 61. the size of which is adjusted by a screw 62.

When the valve 52 is close as sho -vu in the drawings, a certain smallbut continuous flow of air, commonly known as the minimum flow, ispermitted to by-pass the valve through a port 63, the size of which maybe adjusted by a screw 64 having a knurled head which is engaged by aspring detent 65. Clamped to the center of the diaphragm 56 is a rod orstem member 66 guided to slide in aligned apertures in the walls of thecasing 50 and the housing 53. A lever 67 normally bears against the head68 of the rod 66, being held in that position by a spring 69. In

the lower wing 52 of the valve 52 is provided an opening 70 throughwhich the rod 66 passes freely. The rod 66 is preferably made in twosections the section 66 which passes "through the opening 70 beingsmaller in The port 60 is controlled by a valve mounted at one end of asliding valve stem 76, which extends transversely of the casing 50, itsouter end passing through an auxiliary diaphragm 77. The diaphragm 77 ismounted in a housing 78 made up of two parts 79, 80 between the edges ofwhich the diaphragm is clamped and divides the space within the housing78 into chambers 81, 82. The chamber 82 is in communication at all timeswith the atmosphere through a port 83, and the chamber 81 is connectedto the passage in the casing by ducts 84. Clamped at the center of thediaphragm 77 is a sleeve 85 within which the stem 76 slides freely. Theportion 86 of the stem extending through the sleeve 85 is preferably ofa smaller diameter than the remainder of the stem, thus providing ashoulder 87 which abuts the inner end of the sleeve 85. At the outer endof the stem 76 are adjustably secured nuts 88 with which the outer endof the sleeve may abut. The ducts 84 are sealed from the atmosphere by avalve plate 89 carried at the end of the rod 66. The operation of thepower control 30 will be described briefly hereinbelow.

The pressure power control 31 shown particularly in Figs. 6 to 9inclusive comprises a casing 90 having a passage therethrough at oneside of which is provided a housing 91 which, like the housing 53,consists of two parts 92. 93 between the edges of which are clamped theperiphery of a diaphragm 94. The diaphragm 94 divides the housing intotwo chambers 95 and 96 which are connected at all times through aby-pass 97 controlled by a pin 98. The chamber 95 opens directly intothe passage of the casing 90.

Extending transversely across the passage through the casing 90 in aninclined direction is a partition 100 having a central opening 101therethrough. The openinglOl is normally closed by a valve 102 mountedupon a hinge plate 103 carried by a shaft 104 which extends transverselyof the casing 90. A spring 105 normally acts upon the shaft 104 to holdthe valve 102 in the closed position shown in Fig. 7. The hinge plate103 'is connected to a stud 106 fixed at the center of the diaphragm 94by a link 107 which has a pivotal lost motion connection to the plateand stud. Fixed upon the shaft 104is a dog 108 having an inclinedsurface 108 which contacts with the raisededge 109 of the hinge plate103 and insures the proper location of the valve 102.

Mounted on the part 93 of the housing 91 is a small housing 110 having achamber 111 therein closed by a hood 112. Clamped between the edges ofthe hood 112 and the housing 110 is a diaphragm 113 which separates thechamber 111 from the chamber 114 in the hood. To the underside of thediaphragm 113 is secured a plunger 115 which reciprocates freely withinthe chamber 111. -The chamber lll has an extension 1111 therefrom andtheplunger 115 includes a weight. 116

which enters the chamber 111 and a weight 116 which enters the extension.111 extension 111*? is open-t the atmosphere through a port 117 andisConnected to the chamber 96 of the housing 91 througlra passage"111 8;The plunger 115 terminates in a;

taperedvalve 119 which'in oneposition closes the port 117. The chamber116k in the hood 112 is connected by'aconduit 120 to the passage118 andthence to thechamber extension 111 and the chamber 96', whereby thepressureon either side of the diaphragm 113 is equalized.

In the wall of the part 93 are formed a plurality of bosses 121 and anaperture 122v which is in alignment wit-lithe center 7 o f the diaphragm94' and through which projects a sleeve r 123 carried by the housing110. Mounted to reciprocate treely in. the sleeve 123'is a pin 12l,theouter. end of whichmaybe engaged by a latch 125 pivotally mounted on ashaft 126 and normally held in the engaging pos1- t-ion "by-the spring127,; When inthe" positionshown in'FigQ 7 the latch 12 bears againstthetip of the plunger 115 and holds the yalve'llt) raisedso that the port117 is open. It will be noted that in this position the, inner end ofthe pin 124 projects beyond arated byl a diaphragm 136, the periphery ofwhich isclamped between the edges of the casing 132 and cap 13%Carriedby the diaphragm 136 is a stem 137 which extends through anaperture 138 in the cap 134 and I terminates in a button 1393 In thecasing 132 isa second chamber 140 separated from the chamber 133 by a"partition 141 having an aperture 142 therein. [The chambers 1'33and 140.are eachopen tothe atmosphere through ports 1413 and l respectivelyflSecured to the lower end ofthe casing 132by threadingorotherwise isacup1%5,jthe center 1% ofwhich is connectedto the chamber 1&0.

through a port 1&7 and through the nipple 148 with the tube 130 andthence with the chamber 114k in the hood 112 of the-small diaphragmhousing 110 Carried by the diaphragm136is a rod: 150 which maybe integral withthe stem 137 or separate therefromQ The rod 150 extends throughthe chamber 133, the aperture 1 12vand-the chamber lelO and carries atits lower end a disk valve 151 which'may closethe P0141147. A spring 152encircling the. rod 150 normally raises the valve 151-and therebyyieldingly seals the port. I

Mounted in the upper I through the casing 90 is a butterfly valve 155mounted upon a shaft 156. Fixed on one end of-the shaft 156 (see Fig. 6is a locking plate 157 having a slot158 therein. A set screw 159'passesthrough the slot '157 into engagement with the casing90 and thussecures the valve in the proper position in the passage to insurepressure of the amount desired.

" The central station comprises a box or receptacle 160 into whichenterone end of the 1 transmission tube 20and one endof the conduit 25. Thebox 160 is sealed and thus its interior acts as a connecting passage.between the tube and the conduit. The boxhas an opening inits sideclosedby a door 161 hinged upon a. shaft 162 and provided-with a latch 163.normally.closed. The latch16 3 comprises a shank 165 rotatably supportedin a body 166 fixed to the inner face of the door 161:. Secured to theinner'end of the shank'i s a latchplate'l67 and a flat spring .168. The

plate and spring aresecured to theshank by" a screw 169-. The inner endof the shank is "faced off as indicated in dotted lines in Figs. 11 and12 so that it has apositive engagement with the plate 167. A, pin 170holds the spring in position on the plate and a stop171 limits themovement of the latch plate in; either direction; Packing 172 at theinner) edge of the door makes the box air-tight'when the door is closed.

It will be understood that the pressure blower .G andthe vacuum blower Dare in v operation at all times, keeping their respective drums 28 and29 in the proper condition; The valve 38' is normally in the positionshown in Fig. 2*so that the vacuum blower D is in direct connection withthe air tube 25 andthroughthe box 160 with the carrier tube 20. Thevacuum power control 30 is normally in the position shown in Fig.5

whereby a minimum flow of air is maintained in the transmission tube.

aposition shown inFig. 7 with the opening 101 cl'osed-bythe valve102.The door 161 of the box is locked and 'the button 139 of the vent valve130 is in its normal position.

If a carrier is to be sent from substation B to central station? Ag'itisinserted into the outlet 22. The? reduction; of the minimum 'flow bytheinsertion of the carrier causes the control 30 to function infthemannerset forth inthecopending Cowleyapplication which is briefly to c'losetheport 60 bythe action of the diaphragm 77 and open the valve 52 by theaction of the diaphragm 56, thus furnish- I ing a free passage tothevacuum drum and initiating a carrier impelhng flow in the tube end ofthe passage s5 1 A spring 16% acts to hold the door,

7 The pressure blow- 7 er C is also in operation and by reason of theby-pass 97 the diaphragm 94 is held in v in the same direction as theminimum flow. The carrier is thus impelled to the central station Aand'when ejected from the tube 20 the flowis again reduced to theminimum and the arts return to the position shown.

I on the other hand a carrier is to be sent from the central station Ato the substation B, the door 161 is opened and the carrier placed inthe mouth of the tube 20. The door 161 is then closed and secured by thelatch 163 and the button 139 depressed. The depression of the button 139causes the valve 151 to open the port 147 and allow through the tube 130a free connection to the atmosphere of the chamber 114 in the auxiliaryhousing 110. This upsets the equilibrium in the housing and causes thediaphragm 113 to rise, whereupon the plunger 115 lifts the valve 119,opening the port 117. The tip of the plunger is raised above the latchplate 125 which, under the urge of the spring 127, swings into theposition shown in Fig. 7 and prevents the depression or the plunger 115.The equilibrium in the main housing 91 is similarly upset by the factthat the air can escape from the chamber 96 through the passage 118 andconduit'120 into the chamber 114 and thence to the atmosphere and canalso escape through the port 117. The diaphragm 94 under the pressure inthe drum 28 will then swing into the dotted line position shown in Fig.7, resting against the bosses 121 and the valve 102 will be opened,allowing the air to pass through the casing 90 toward the conduit 25.This rush of air swings the valve 38 from the position shown in Fig. 2into that shown in Fig. 3 and allows the air under positive pressure toenter the conduit freely. ,A carrier impelling flow is thus initiated inthe tube 20 and the carrier impelled to the station B.

As the diaphragm 94 takes the dotted line position of Fig. 7, it bearsagainst the end 128 of the pin 124 and swings the latch 125 out ofengagement with the tip of the plunger so that the latter will descendby reason of the weights thereon. The button 139 is in the meantimereleased after there has been introduced an amount of air under pressureslightly more than that necessary to cause the carrier to complete itsjourney. The rod 150 then returns to its normal position, under the urgeof the spring 152, closing the port 147 and thus breaking the connectionof the chamber 114 to the atmosphere through the tube 130. The pressurein the chamber 96 will then build up until the diaphragm 94 returns toits normal position closing the opening 101 and cutting off the supplyof air underpressure to the conduit 26 and trans mission tube 20. Thevalve 38 will return to its normal position as soon as the supply of airunder positive pressure is cut off.

It will be noted that when the carrier impolling flow. is being createdin the tube 20 by positive pressure and the valve 38 is bear- 7 ing aainst the seat 37 as in Fig. 3, the valve 43 wi I open the port 44, thuspermitting the entry of air from the atmosphere to prevent building upthe vacuum in the tube 27 which would cause the control30 to operateunnecessarily. V V 1 While certain features of the selected embodimenthave been shown and described in detail, itwill be understood that I amnot limited to such features per se and that my invention covers anysubstitutions or equivalents that come within the spirit and scope of myinvention as set forth in the following claims.

I claim: I

1. In a pneumatic dispatch system, two stations, a single transmissiontube connecting said stations, means normally maintaining a minimum flowof air through the tube, and responsive to a reduction in such flowresulting from the insertion of a carrier in the tube,,for initiating acarrier impelling flow through the tube in one direction at least andmeans for terminating said minimum flow and initiating a carrierimpelling fiow through the tube in the opposite direction.

2. In a pneumatic dispatch system, two stations, a single transmissiontube connecting said stations, means normally maintaining a minimum flowof air through the tube, and responsive to a reduction in such flowresulting from the insertion of a carrier in the tube, for initiating acarrier impelling flow through the'tube in one direction at least andmanually controlled means for terminating said minimum flow andinitiating a carrier impelling flow through the tube in the oppositedirection. a r

3. Ina neumatic dispatch system, two stations, a single transmissiontube connecting said stations, means normally maintaining a minimum flowof air through the tube and manually controlled means for terminatingsaid minimum flow and initiating a carrier impelling flow through thetube in the direction opposite to that of the minimum flow.

4. In a pneumatic dispatch system, two stations, a single transmissiontube connecting said stations, means normally maintaining a minimum flowof air through the tube and means for terminating said minimum'flow andinitiating a carrier impelling flow through the tube in the directionopposite to that of the minimum flow.

5. In a pneumatic dispatch system, two

stations, a single transmission tube connect- I ing said stations, meansnormally maintaining a minimum flow of air through the tube, said meansincluding a valve and means for shifting the position of the valvethereby terminating the minimum flow and for initiating a carrierimpelling flow through the tube in one direction at least.

6. In a pneumatic dispatch system, two

7 stations, a single transmission tube connecting said stations, meansnormally maintainmg a minimum flow of air through the tube, said meansincluding a valve and manually controlled means for shifting theposition of the valve thereby terminating'the mini.- mum flow and forinitiating a carrier impelling flow throughtlie tube in one direction atleast.

In a pneumatic dispatchv system, two stations, a single transmissiontubeconnecting said stations, means normally maintains ing a minimumflow of air through the tube,

said means including a valve and manuallycontrolled means for shiftingthe position 01": the valve thereby terminating the minimum flow and fornitiating a CZIITIQI impelhng V 7 flow through the tube in the directionopposite to that of the minimum flow.

8. In a pneumatic dispatch system, two stations, a single transmissiontube connecting said stations, means normally maintaining a minimum flowof air through the tube, said means including valve and means forshifting the position of the valve thereby terminating the minimum flowand for initiating a carrier impelling flow through the tube in thedirection opposite to that of the minimum flow. 7

9. In a pneumatic dispatch system, two stations, a single transmissiontube connecting said stations, means normally maintain ing a minimumflow of air through the tube said means lncluding a valve, means, re-

; sponsive to a reduction in such flow resulting a source 01" negativeair pressure, a source of positive air pressure, tubes connecting saidsources with the conduit, a valve at the uncture of said tubes andconduit normally closing the tube from the source of positive airpressure, the tube from the source of negative air pressure having anopening therein,

a valve normally closing said opening, a

power control for initiating a carrier impelling flow through thetransmission tube in one direction upon the insertion of a carriertherein and a manually operable power control for shifting said valvesfrom their normal position and initiating a carrier impelling flowthrough thetransmission tube in the other direction. a

ll- I -apneumatic dispatch system, two stations, a s ngle, transmissiontube connecting said stations, one ot-said station including a box inwhich one end of the tube terminates, a conduit leading from the box, a

source of negative air pressure, a source of positive air pressure,tubes connecting said sources with theconduizt, a valve at the junctureof said tubes and conduit normally clgs ,ing the tube fromvthe source ofpositive air pressure, the tubet'rem the sourceot negative valvenormally closing saidopenin-g, a power controlassooiated with the sourceoinegative air pressure for initiatinga carrier impelling flow throughthe transniission tubein One direction upon the insertion of a carriertherein and a manually operable power-control associated with thesource'ot positive air pressure torshifting said valves from theirnormal air pressure having an opening therein, a

position. terminating the carrier impelling flow above mentioned andinitiatinga carrierimpellingflow through the transmission tube intheopposite direction. p 12. In a pneumatic dispatch system, two stations,a single transmission tube connecting said stati0ns, one of saidstations including a box in whioh'one end otthe tubeterminates, aconduit leading from the box, a

source of negative air pressure, a source of sources withzthe conduit, avalve at the juncture of said tubes and conduit normally clos- 'ing thetube from the source of positive air pressure, the tube from the sourceof negative air pressure having an opening therein, a valvenormally-closing said opening, a power control associated with thesource of negative air pressure for normally maintaining a minimum flowof air through the transmission tube and responsive to a as positive airpressure, tubes connecting said reduction in such flow resulting fromthe 'in- V sertion of a carrier in such tube at one'station, forinitiating a carrier impelling flow through the tube toward the otherstation and a manually operable power control for shifting said valvesfrom their'normal positions and initiating'a carrier impelling flowthrough the tube in the opposite direction.

13. In a pneumatic dispatch system,tw0 stations, a single transmissiontube connecting said stations, one of said stations including a box inwhich one end of the tubeterminates, a conduit, leading fromv the box, asourceof negative air pressure, a source of positive air pressure, tubesconnectingjsaid sources with the conduit, a valve at the juncture ofsaid tubes and conduit normally closing the tube from the source ofpositive air pressure, the tube from the source of negative air pressurehaving an opening therein, a

valve normally closing said opening, and

means for shifting said valves out of their normal positions thusopening the tube from the source of positive air pressure and closingthe tube from the source of negative air pressure and uncovering theopening.

14. In a pneumatic dispatch system, two stations, a single transmissiontube connecting said stations, one of said stations including a box inwhich one end of the tube terminates, a conduit leading from the box, a

source of negative air pressure, a source of positive air pressure,tubes connecting said sources with the conduit, a valve at the junctureof said tubes and conduit normally closing the tube from the source ofpositive air pressure, the tube from the source of negative air pressurehaving an opening therein, a valve normally closing said opening, saidvalves being vjoined to move as a unit and means for shifting the firstmentioned valve to open the tube from the source of positive airpressure and close the tube from the source of negative air pressure,such movement cansin% the second valve to uncover the opening.

igned by me at Syracuse, New York, this thirty-first day oi- July, 1928.

MERTON L. EMERSON.

